Building automation systems (BAS) are used to coordinate, manage, and automate control of diverse environmental, physical, and electrical building subsystems, particularly HVAC and climate control but also including security, lighting, power, and the like. One example of a building automation system and architecture that provides an intelligent control system via a dynamically extensible and automatically configurable architecture is disclosed in U.S. Publication No. 2007/0055760, of common assignee with the present application.
One common element in many BAS installations are variable air-volume (VAV) elements that typically include one or more air sources and air distribution boxes, also known as VAV boxes, that are used to supply only as much conditioned air to a space as is necessary to maintain the desired environmental conditions in that space. A large building or campus can contain multiple air sources that deliver air to multiple VAV boxes that in turn control the air flow to individual spaces in a given building. For many reasons, one of which being the simple variance in size or volume of each space to be conditioned, it is necessary to configure or balance the amount of air each VAV box provides to an assigned space. Balancing the system to provide the appropriate amount of airflow can help to improve the efficiency of the building's environmental controls as well as maintain the comfort of any occupants of the space. While balancing a VAV system with a single air source and a few associated VAV boxes is relatively straightforward, the complexity of the task increases substantially when multiple air sources are tied to multiple VAV boxes in a large system. Even though the relationship between each individual VAV box and its corresponding air source in a multi-air-source building may be clearly depicted in a building's design documents, transferring those relationships into a digital BAS environment requires laborious programming or data entry that is subject to human error as well as discrepancies that may exist between the design documents and the actual building configuration and wiring.
A variety of techniques exist for balancing VAV boxes and air sources. Examples include those described in U.S. Pat. Nos. 5,251,815 and 5,341,988, each having a common assignee with the present application. Another discussion of a variable air-volume balancing system is disclosed in U.S. Pat. No. 5,605,280 to Hartman. However, even with these techniques, fully configuring a large system is still generally a labor-intensive task that varies with each system implementation, and requires the manual programming or association of VAV boxes to each air source. In the case of multiple air sources that supply multiple VAV boxes in a multi-space building the associated relationships can become even more complex and require additional efforts to achieve the proper balance in the system. Upgrading, expanding, and updating or removing VAV system components are also complex tasks, as the existing BAS must be reconfigured and rebalanced to recognize and incorporate any changes.
Accordingly, a need remains for an intelligent BAS having the capability to automatically map and associate the various VAV boxes located in a structure with multiple air sources providing conditioned air to that structure.